RESUMO
Three species of the genus Euphoriomyces (Laboulbeniales) were found newly from Korea. E. agathidii (Maire) Tavales was collected from Agathidium sp. (Leiodidae, Coleoptera). The characteristic traits of this species are the distal portion of the primary axis composed of 5~11 superposed layers and bearing more or less the elongated appendages. E. cybocephali (Thaxter) Thaxter was collected from Pseudocolenis hilleri Reitter (Leiodidae, Coleoptera). The primary axis of this species composed of 5~9 superposed layers is simple, not branched and a single antheridium occurs on the apex of the secondary axis. E. sugiyamae Majewski was collected from Scaphisoma rufum Achard (Scaphidiidae, Coleoptera). This species is very unique in having the antheridia formed as coner cells with lateral necks.
RESUMO
Summary Bacilluscatabolite control protein (CcpA) mediates carbon catabolite repression (CCR) by controlling expression of catabolite responsive (CR) genes or operons through interaction with catabolite responsive elements (cres) located within or outside of CR promoters. Here, we investigated how CcpA inhibits the transcription of CR promoters in vitro. CcpA has different affinities for different cres, but this does not correlate with its ability to inhibit transcription. In the amyE promoter, which overlaps a CcpA binding site (amyE cre centred at +4.5), CcpA does not prevent RNA polymerase (RNAP) binding to the promoter; it may even interact with RNAP. Inserting non-integral turns of helix (1.5 and 2.5) between the amyE promoter (-10 hexamer) and the amyE cre relieved CCR of amyE expression. In the xyl operon, despite the downstream location of its cre (a major cre centred at +130.5), CcpA blocked transcription initiation, not elongation (roadblock) at the site of the cre. Taken together, our results strongly suggest that CcpA requires interactions with RNAP to inhibit transcription.
Assuntos
Bacillus megaterium/metabolismo , Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Ligação a DNA/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Regulação Bacteriana da Expressão Gênica , Proteínas Repressoras/metabolismo , Transportadores de Cassetes de Ligação de ATP/química , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Bacillus megaterium/enzimologia , Bacillus megaterium/genética , Bacillus subtilis/enzimologia , Bacillus subtilis/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Sequência de Bases , Proteínas de Ligação a DNA/farmacologia , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Proteínas Repressoras/farmacologia , Transcrição GênicaRESUMO
Differential display (DD) PCR was applied to identify genes regulated by anorexia (anx) in mouse brain. Of the four apparently differentially expressed genes, three (H2-H4) had high homology with known genes such as apoptotic protease activating factor 1 (Apaf 1), adenylate cyclase 6 (Adcy 6), and myelin proteolipid protein (PLP). H1, designated as HIPA1, had a homology with unknown function gene fragments. Northern blot analysis confirmed HIPA1 expression induced by anorexia. A 1579 bp full-length cDNA of HIPA1 was isolated from a mouse brain cDNA library using a probe from the differentially displayed H1 fragment. Sequence analysis showed that HIPA1 had 98.7% homology to mouse hippocampus cDNA. In situ hybridization demonstrated that the HIPA1 mRNA was highly up-regulated in the hippocampus of anx/anx mouse brain.
